Stabilization of iodopropynl compounds

Abstract

A highly stable liquid formulation having broad spectrum preservative properties which constitutes an admixture of a dialkanol-substituted DMH, an iodopropynyl compound, a stabilizer of a hydantoin, urea or derivative thereof, and a hydroxyl solvent. Preferably the constituents are dimethyloldimethylhydantoin, 3-iodo-2-propynylbutyl carbamate, dimethylhydantoin, and a glycol solvent. The preservative preferably has a total formaldehyde content of 5% and less than 0.2% of free formaldehyde. The composition is prepared by successively admixing the dialkanol-substituted dimethylhydantoin and the stabilizer, the hydroxyl solvent, and the iodopropynyl compound. Also described is a stabilized iodopropynyl compound preferably containing dimethylhydantoin as the stabilizer.

We claim: 
     
       1. A stabilized iodopropynyl solution which consisting essentially of an iodopropynyl compound and a stabilizer which is (i) a hydantoin or derivative thereof represented by Formulas III, IV, or V: ##STR8## wherein R 1  to R 4  are independently selected from H, C 1  to C 22  ; ##STR9## wherein R 1  to R 5  are independently selected from H or C 1  to C 22  ; or ##STR10## wherein R 1  to R 6  are independently selected from H, CH 3 , C 2  H 5  or C 3  H 7  ; or (ii) urea or derivative thereof represented by Formula VI: ##STR11## wherein R 1  to R 4  are independently selected from H or C 1  to C 12  ; the ratio of said stabilizer to iodopropynyl compound being from 150:1 to 0.05:1 and sufficient to chemically stabilize the iodopropynyl compound.   
     
     
       2. The solution of claim 1 wherein the stabilizer is the hydantoin or derivative thereof represented by formula III wherein R 3  and R 4  are both methyl. 
     
     
       3. The solution of claim 1 wherein the iodopropynyl compound is iodo-2-propynylbutyl carbamate and the stabilizer is dimethylhydantoin. 
     
     
       4. A liquid composition comprising an iodopropynyl compound and a stabilizer which is a hydantoin or derivative thereof represented by Formulas III, IV, or V: ##STR12## wherein R 1  to R 4  are independently selected from H, C 1  to C 22  ; ##STR13## wherein R 1  to R 5  are independently selected from H or C 1  to C 22  ; or ##STR14## wherein R 1  to R 6  are independently selected from H, CH 3 , C 2  H 5 , or C 3  H 7 , the ratio of said stabilizer to iodopropynyl compound being from 150:1 to 0.05:1 and sufficient to chemically stabilize the iodopropynyl compound. 
     
     
       5. The composition of claim 4 wherein the stabilizer is the hydantoin or derivative thereof represented by formula III wherein R 3  and R 4  are both methyl. 
     
     
       6. The composition of claim 4 wherein the iodopropynyl compound is iodo-2-propynylbutyl carbamate and the stabilizer is dimethylhydantoin.